Rotadiscus
Extinct genus of disc-shaped animal
From Wikipedia, the free encyclopedia
Rotadiscus is a genus of discoidal animal known from the Cambrian Chengjiang biota[3] and classified with the eldonioids.[2]
| Rotadiscus Temporal range: | |
|---|---|
| |
| Fossil of Rotadiscus | |
Scientific classification  | |
| Kingdom: | Animalia |
| Stem group: | Ambulacraria |
| Clade: | †Cambroernida |
| Class: | †Eldonioidea |
| Family: | †Rotadiscidae |
| Genus: | †Rotadiscus Sun & Hou, 1987 |
| Type species | |
| R. grandis Sun & Hou, 1987 | |
| Synonyms[2] | |
| |
As with other eldonioids, it was originally thought to have been pelagic, but is now thought to be benthic.[4]
In addition to the type species R. grandis, two other Rotadiscus species have been proposed. The first is known only from one complete juvenile specimen and a few fragments, and was originally described as "Brzechowia sp." It remains without a formal species name, but has been transferred to Rotadiscus.[5] The species initially described as R. guizhouensis has since been reassigned to the genus Pararotadiscus.[2]
A 2023 cladistic analysis based on new fossils places Rotadiscus, along with other eldonioids, as stem-group ambulacrarians in the clade Cambroernida.[6]
